Housing, battery cell, battery and electric apparatus

A case, comprising:

• a case body for accommodating an electrode assembly;
• and
• a pressure relief structure, comprising a plurality of first pressure relief grooves disposed at intervals on the case body along a circumferential direction of the case body, wherein the first pressure relief grooves are in linear shape and disposed substantially perpendicular to the circumferential direction;
• wherein the pressure relief structure further comprises a second pressure relief groove disposed on the case body, each of the first pressure relief grooves intersects with the second pressure relief groove to form a plurality of opening positions;
• wherein the pressure relief structure further comprises a plurality of third pressure relief grooves and a plurality of fourth pressure relief grooves, each of the first pressure relief grooves is correspondingly provided with a third pressure relief groove and a fourth pressure relief groove, the third pressure relief groove and the fourth pressure relief groove both intersect with the first pressure relief groove and are disposed at either side of the second pressure groove respectively;
• wherein the case body is configured to rupture from an opening position along a first pressure relief groove when pressure or temperature inside the case body reaches a threshold, so as to release the pressure inside the case body.